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Angular 5 HttpClient Post List to Web Api - always null?

由 旧城冷巷雨未停 提交于 2020-01-05 06:44:05
问题 The setup is Angular 5 and .net core Web Api. At the controller, model binding always results in null while trying to bind to a complex object. Code is provided below. This example is adapted from another SO answer . but its not working for me. Controller: [Route("demopost1")] [HttpPost] public async Task < IntResultEntity > DemoPostList1([FromBody]DemoPostViewModel payload) { return await Task.FromResult(new IntResultEntity { Result = 0 }); } Models: public class DemoPostModel { public

C# NullReferenceException was unhandled - Object reference not set to an instance of an object

由 戏子无情 提交于 2020-01-05 06:43:08
问题 I'm trying to create a application using Windows Forms in C#, however I keep getting an error stating: NullReferenceException was unhandled - Object reference not set to an instance of an object It's pointing to the line which has this code on: carBootSaleList.AddCarBootSale(newCarBootSale); The method I have on the forms interface: CarBootSaleList carBootSaleList; public void AddCarBootSale() { AddNewCarBootSale addForm = new AddNewCarBootSale(); if (addForm.ShowDialog() == DialogResult.OK)

Given an array of arrays, how can I replace all empty values with 0?

由 末鹿安然 提交于 2020-01-05 05:30:10
问题 Example array $myArray[0] = array('23', null, '43', '12'); $myArray[1] = array(null, null, '53', '19'); $myArray[2] = array('12', '13', '14', null); All nulls should be replaced with 0. I was hoping someone would have an efficient way of doing this, perhaps a built in PHP function that I am unaware of. 回答1: You could use the array_walk_recursive function, with a callback function that would replace null by 0 . For example, considering your array is declared this way : $myArray[0] = array(23,

Finding a Pointer to NULL

由 拜拜、爱过 提交于 2020-01-05 04:33:07
问题 I have int* foo[SIZE] and I want to search it for the first element that points to NULL . But when I do this: std::find(foo, foo + SIZE, NULL) I get the error: error C2446: '==' : no conversion from 'const int' to 'int *' Should I just be using static_cast<int*>(NULL) instead of NULL ? C++11 solves this via nullptr but that's not an option for me in C++03 回答1: tl;dr: Use nullptr , or define your own equivalent. The problem is that NULL is some macro that expands to an integral constant

Can Maximo formulas return null?

由 社会主义新天地 提交于 2020-01-05 04:13:09
问题 The bounty expires in 4 days . Answers to this question are eligible for a +50 reputation bounty. User1973 wants to draw more attention to this question. In Maximo 7.6.1.1: I have an attribute formula on a persistent field called WORKORDER.X . The field type is decimal, length is 18, and scale is 10. The formula is meant to do this: If WOSERVICEADDRESS.LONGITUDEX is not null, use it Else, if ASSET.X is not null, use it Else, if LOCATION.X is not null, use it This is the expression I've come

Mybatis

由 主宰稳场 提交于 2020-01-05 00:32:14
一对一，一对多，多对多 一对一的关系映射 创建表和相关数据 CREATE TABLE houseinfo ( houseid int(11) NOT NULL AUTO_INCREMENT, housedesc varchar(32) DEFAULT NULL, typeid int(11) DEFAULT NULL, monthlyrent decimal(10,2) DEFAULT NULL, publishdate datetime DEFAULT NULL, PRIMARY KEY ( houseid ) ) ENGINE=InnoDB AUTO_INCREMENT=49 DEFAULT CHARSET=utf8mb4; > insert into `houseinfo`(`houseid`,`housedesc`,`typeid`,`monthlyrent`,`publishdate`) values (1,'领包入住靠地铁站',1,'1000.00','2019-12-11 14:00:03'),(2,'环境优雅',2,'3200.00','2019-12-11 14:00:03'),(3,'豪华装修',3,'5000.00','2019-12-11 14:00:03'),(4,'1',1,'5.00','2019-12-20 20:46:03'),(5,'a',3,

Why am I getting error Undefined method `name' for nil:NilClass with Ruby on Rails?

由 倖福魔咒の 提交于 2020-01-04 21:35:54
问题 I thought methods such as name and email were default in rails? In my static pages view, in profile.html.erb I have: <% if logged_in? %> <% provide(:title, @user.name) %> <% else %> <% provide(:title, 'Profile')%> <% end %> I put in my static_page_controller def profile @user = User.find_by_remember_token(:remember_token) end When I go to the console User.find_by_remember_token("actualtoken").name returns me the appropriate users name, but :remember_token does not. How do I make :remember

ConcurrentLinkedQueue多线程安全的并发删除队列元素

由 流过昼夜 提交于 2020-01-04 11:52:55
1、remove方法 public boolean remove(Object o) { if (o != null) { Node<E> next, pred = null; for (Node<E> p = first(); p != null; pred = p, p = next) { boolean removed = false; E item = p.item; if (item != null) { if (!o.equals(item)) { next = succ(p); continue; } removed = p.casItem(item, null); } next = succ(p); if (pred != null && next != null) // unlink pred.casNext(p, next); if (removed) return true; } } return false; } 2、初始化队列 3、线程过来 执行remove("王五") 1）点击下面的first() for (Node<E> p = first(); p != null; pred = p, p = next) { first()方法如下： Node<E> first() { restartFromHead: for (;;) { for (Node<E>

Checking MySQL NULL values with PHP

由 非 Y 不嫁゛ 提交于 2020-01-04 06:35:29
问题 This is how my table looks like.. id col1 col2 --------------- 1 a x 2 NULL y 3 NULL z 4 NULL t col1 has a default value of NULL . I want to use col1 data If col1 is not null, otherwise use col2 data. function something($col1,$col2) { if(is_null($col1) == true) $var = $col2 else $var = $col1 return $var; } function something2($col1,$col2) { if($col1 === NULL) $var = $col2 else $var = $col1 return $var; } Here is my problem. Both of these functions returns $col2 values. But as you can see in

Checking MySQL NULL values with PHP

由 心不动则不痛 提交于 2020-01-04 06:34:28
问题 This is how my table looks like.. id col1 col2 --------------- 1 a x 2 NULL y 3 NULL z 4 NULL t col1 has a default value of NULL . I want to use col1 data If col1 is not null, otherwise use col2 data. function something($col1,$col2) { if(is_null($col1) == true) $var = $col2 else $var = $col1 return $var; } function something2($col1,$col2) { if($col1 === NULL) $var = $col2 else $var = $col1 return $var; } Here is my problem. Both of these functions returns $col2 values. But as you can see in
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